You’re right. What you may not realise is that this offer isn’t for folks like you and I, but for “allies” (as Jason Cohen, founder of WPEngine puts it). That is, folks who buy into these lifetime / multi-year deals are a different kind of a customer, but they do exist. In fact, Cohen argues that these “allies” vote both with the wallet and their time (quite significantly more than regular customers otherwise might) and so, are worth pursuing (even worth paying special attention to, for example, their feature requests).
I tell Vishnu (one of the co-founders at Ente) this every single time I see him. Ente know this, and my wish is that the economics work out over a period of time so that folks like you & I (who feel uncomfortable paying more despite the clear value-add) can switch without any hurdle.